Question

The pH of pure water or natural solution at ${50}^{o}C$ is ($p{K}_w$ = 13.26 at ${50}^{o}C$)

• A. 7
• B. 7.13
• C. 6
• D. 6.63

Answer 1

The correct option is D 6.63

$\left[H^{+}\right]\left[O{H}^{-}\right]={10}^{-13.26}$

For pure water,

$\therefore \left[H^{+}\right]=\left[O{H}^{-}\right],\therefore [H^{+}{]}^2={10}^{-13.26}$

$\left[H^{+}\right]=2.34\times {10}^{-7}$

$pH=6.63$